Phonograph sound reproducer



Oct. 20, 1931.

J. H. BUCHANAN PHONOGRAPH SOUND REPRODUCER Filed June 19. 1929 Oct. 20, 1931.

J. H. BUCHANAN PHONOGRAPH SOUND REPRUDUCBR Filed June 19. 1929 2 Sheets -Sheet 2 Patented Oct. 20, 1931 JAMES H. BUCHANAN, F LOS ANGELES, CALIFORNIA PHONOGRAPH SOUND REPRODUCER Application led June 19, 1929. Serial No. 372,010.

My invention is a phonograph sound reproducer, which by the medium of light and electrical yvibrations transforms the vibrations of the stylus into sound.

A main obj ect of my invention is reproducing sound from a phonograph record, by

utilizing the vibrations of the stylus to control a fluctuating light and utilizing such light in connection with a photoelectric cell or the like to reproduce sound.

Another object of my invention is an apparatus and method' of reproducing sound from a phonograph record, by causing the vibrations of the stylus to cause a vibratory interruption of the beam of light and to use such beam of light in the reproduction of sou-nd. i

A more particular object of my invention is utilizing 'a phonograph stylus which is vibrated by a record, causing such stylus to vibrate a light interruptor which is positioned formlng devlce mounted above a phonobetween a source of light and a photoelectric cell and then utilizing the current controlled by the cell to reproduce sound.

Another object of my invention is in mounting the apparatus having the stylus1 the light interrupter, the source of light and v the photoelectric cell, on a carriage which is movable over a phonographic record, whereby the vibrations of the stylus causes a vibration of the light interrupter and thence the photoelectric cell controls the development of the sound.

In this connection a more detailed object of my invention is moving the carriage and stylus by a screw operated from the turntable spindle of a disk type of record rotator, so that the carriage follows the grooves on the record and thus produces the recording complete from the periphery to the center portion of the disk.

In constructing my invention I preferably have a pair of tracks located on opposite sides of the turntable for using a disk type of record and slidably mounted on these tracks I have a bridging frame which has the carriage thereon. The carriage contains the light interrupter which is in the form of a light vibrating reed which vibrates across a narrow' slot under the action of the stylus,

. amplifying Vand is adapted to engage the grooves of the record. The carriage also mounts a lamp, a suitable lens system and a photoelectric cell with a small amplifier positioned adjacent 4the cell.

The screw for shifting the carriage has a mounting yon one side of the turntable allowing a universal movement of one end of the screw. The other end of the screw has a .gearing which may be connected to the spindle of the turntableand thus rotate the screw to give the carriage a transversemovement Jfrom kthe periphery towards the center kof the disk, whereby the stylus may correctly pick up the vibrations cut .into the record.

The current from the photoelectric cellafter is reproduced by a loud speakerA or the like.

. My invention is illustrated in the accompany'ing drawings, in which,

Figure 1 is a plan of the vibration transgraphic turntable;

Fig. 2 is a vertical section taken on the -line 2-2 of Fig. 1, in the direction of the arrows;

Fig. 3 is a vertical section on the line 3-3 of Fig. 1`, inthe direction of the arrows;

Fig. 4 is a horizontal section substantially `on the line 4 4 of Fig. 3 in the direction lplifier, suitable for connection to a loud speaker.

In the drawings a phonograph cabinet is indicated by the numeral 11 having a top 12 and on this top there is mounted the usual rotatable turntable 13. This turntable is mounted on a rotatable spindle 14. The table has the usual felt covering 15 or the like. The phonograph disk is indicated by the numeral 16. This is shown as the type fhaving the 'zigzag or lateral recording thereon.

An instrument box 17 is mounted on a carriage 18, this carriage having side bars y19 with curled bearing ends 2O and which ends slide ontracks 21 which are illustrated,YA as being round barsand such bars are supported on pedestals 22 extending upwardly from the top of the phonograph cabinet or table. The instrument box is illustrated as being slightly spaced from the carriage structure, which structure in reality may be merely a continuation of the side bars 19. The bottom of the bars have studs 23 extending downwardly and the spring 24 between the heads of the studs and the bottom of the bars 19.

The shifting of the box across the vertical record is accomplished by means of a lead screw 25 which at one end has a ball 26 mounted in the spherical bearing 27 this bearing having a removable cap 28 and being mounted on a pedestal 29 extending upwardly from the top of the vertical cabinet. The other end of the screw has an arcuate frame 30 connected thereto, this frame forming a journal 31 for the inner end of the screw 25 and also forming a journal havinY a vertical stub shaft 32. This stub sha has a socket member 33 thereon adapted to fitover the top of the spindle 14, which spindle is illustrated as having a slot 34 so that the. pin 35 attached to the socket extends downwardly into 'the slot. Therefore the rotating movement of the spindle 14 rotates the socket 33 and hence the stub shaft 32. A bevel ear 36 on the stub shaft meshes with a vbeve gear 37 on the screw 25, there being a collar 38 preferably secured to the screw Vand holding the gears in proper meshing relation. By this construction the screw 25 with the carriage and instrument box may be lifted up, pivoting on the ball 26 mounted in the spherical bearing. This allows changing records and when the screw is again lowered so that the socket 33 interfits with the spindle 14 the rotation of the spindle and hence the turntable and record causes a rotation of the screw 25. There is a half nut 39 secured to the carriage or to the box structure and meshing with the upper portion of the threads on the screw 25, so that when the screw rotates the instrument box is shifted in a radial direction in reference to the record.

The box has a depending structure with a chamber 40 in which there is mounted a ivot 41 for a vibrating needle or reed 42. This needle or reed extends downwardly through aslot 43 on the bottom of the dependin structure and has a socket structure 44 in w ich may be engaged a stylus 45 held in place in any suitable manner. The stylus is preferably removable. A partition 46 has a vertical slot 47 therein so that the needle or 42 may vibrate across the front of this slot.

l A source of light is indicated by the lamp 48 mounted in one end of the instrument box adihaving its light reflected by a reiiector 49 passing through an optical system of lenses aiid then through the slot 47 and being concentrated on a photoelectric cell 51. The lightenters the window 52 of the cell. The

cell is wired to a small amplifier 53 adjacent thereto, also preferably mounted in the box and to simplify the illustration, electric leads 54 are indicated as leading to an electro-mag netic sound producing unit 55 which has a horn or the like 56 connected thereto.

In Fig. 5 I illustrate one type of electric connection tothe photoelectric cell. An energizing source of power is indicated by the battery 57, there being circuit leads 58 and 59 from the battery through a resistance (3() to the terminals of the photoelectric cell. The current Hows to a tube amplifier 60 havingr a connection (51 to the grid of the tube. The tube is energized by a battery (i2, there being a resistance (S3 in the battery circuit.

My invention as above mentioned, is adapted to be used particularly with records having a lateral or zigzag sound recording thereon. My invention may be utilized for disks in which the sound record starts at thc outside and works towards the inside and in which the record starts on the inside and `works outwardly towards the outside. After the disk is positioned the screw is connected to the spindle to be driventhereby and theinstrument box with its carriage is mounted on its rails or the equivalent so that when the screw rotates and engages the half nut 39, the instrument box is shifted. The screw is arranged to synchronize with the grooves in the record which are cut in a spiral manner on the disk.

As the disk rotates the stylus 45 is vibrated and this causes a rocking vibration of the reed 42, this operating across the slot or aperture 47, whereby the light from the lamp 18 lis interrupted in passing through the said slot. The light rays are picked up by the photoelectric cell which has its electrical functions varied and transmits a varying electric current preferably through an amplifier to a loud speaking horn. Hence the mechanical vibrations set up by the phonograph record are through the action of changes of light caused to form an electrical fluctuating current having characteristics similar to the wave form of the sound ware on the record. Therefore the electric current may be utilized to operate a loud speaker.

By my equipment it will be seen that I may reproduce sounds by changing the mechanical vibration of the stylus into the vibration of a light intercepting device which causes a vibration in a beam of light and this beam of light affecting the photoelectric cell causes a transposition into an electrical vibration, which electrical vibration is transformed into sound. Thus my invention comprises not only the apparatus but the method of reproducing sound from a mechanical vibration derived from a phonographic record to a vibration of light and then by electrical vibrations and thencethe sound.

Various changes may be made in the prinil! lciples of my invention Vwithout departing from the spirit thereof as set forth in the description, drawingsv and claims.

I claim:

l. A sound reproducer comprising in combination a turntable adapted to support a phonograph record and having a rotatable spindle, a pivotally mounted screw, a stub shaft adapted to engage the spindle, a driving connection between the Stub shaft and the screw, a vibratory device having a mounting shiftable by the screw, means to direct a beam of light on an electric light responsive device, the vibratory device being positioned to intercept the beam and cause a variation of the illumination of the light responsive device.

2. A sound reproducer as claimed in claim l, the screw and the stub shaft having an interconnection whereby the bodily shifting of the screw may engage or disengage the stub shaft from the said spindle.

3. A sound reproducer comprising in combination a rotary turntable for a phonograph record, a rotary spindle, a screw pivotally mounted at one end to have a pivoting and a rotary motion, a stub shaft connected to the screw and adapted to engage the spindle to be driven thereby, a driving connection between the stub shaft and the screw, a supporting track, a carriage mounted thereon and having an engagement with the screw, a source of light in the carriage, adapted to project a beam of light, an electric light responsive device to receive the beam, a mechanical vibratory device having a part thereof to engage the record and another part to intercept the beam of light.

4. A sound reproducer comprising in combination a rotatable spindle having a rotatable disk to support a phonograph record, a socket structure fitting thereon and having a vertical stub shaft journaled therein, a horizontal lead screw having a pivotal mounting beyond the periphery of the disk, a drive connection from the stub shaft to the said screw, an instrument box havin a connection to said screw and with a vibratory stylus to engage a record, a reed connected to the stylus, a source of light with means to transmit a beam of light past the said reed, and means to receive and reproduce electrical signals from the transmitted light.

5. A sound reproducer comprising in combination a cabinet top having a rotatable spindle with a turn table thereon for a disk, a pedestal secured to the cabinet top and having a 'lead screw swivelly connected thereto, a frame connected to the end of the lead screw and having a socket with a stub shaft therein, a geared connection from the screw to the stub shaft and means to connect the stub shaft to the spindle, a pair of guide tracks, an enclosed carriage mounted thereon, a structure having a vertical slot and having a stylus to engage a record, a source of light, a lens to form a beam of light, a photoelectric cell, and an amplifier mounted in the cabinet, the carriage having a support on the said tracks and having a driving connection with the said screw.

6. A sound reproducer comprising in combination a cabinet top having a rotatable spindle with a disk for a record, a pedestal k0n the cabinet, a lead screw swivelly connected to the pedestal and having a frame at its opposite end, with a stub shaft ournaled in said frame, means to connect the stub shaft to the spindle, a geared connection between the stub shaft and the screw, a pair of guide tracks parallel to the screw, an enclosed carriage mounted on said tracks and having a driving connection with said screw, a vibratable device in the carriage operated by a stylus from a record, a source of light forming a beam, a light electric sensitive device, said vibrating device varying the beam of light in accordance with the vibration of the stylus.

In testimony whereof I have signed my .t 

